1. Field of the Invention
The present invention pertains to a method for improving cure speed retention of thiol-ene formulations and to thiol-ene formulations with improved cure speed retention on aging.
2. Definitions
As used herein:
A polyene is a compound having a plurality of olefinically unsaturated groups. PA1 A polythiol is a compound having plurality of organic thiol groups. PA1 A thiol-ene composition is a mixture of a polyene and a polythiol formulated to cure at least predominately by addition of thiol groups across the olefinic double bond of the polyene. PA1 Norbornenyl groups, as used herein, are broadly defined to encompass organic functional groups of the formula: ##STR1## where Q is CR.sub.2.sup.1, O, S, NR.sup.1 or SO.sub.2, R.sup.1 is H or alkyl; and m is 0-10. Thus the term should be understood to encompass, in addition to true norbornenyl groups, various substituted analogs, nadic groups and various other cyclopentadiene Diels-Alder polyadducts.